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Capellmann S, Kauffmann M, Arock M, Huber M. SR-BI regulates the synergistic mast cell response by modulating the plasma membrane-associated cholesterol pool. Eur J Immunol 2024:e2350788. [PMID: 38708681 DOI: 10.1002/eji.202350788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 04/24/2024] [Accepted: 04/26/2024] [Indexed: 05/07/2024]
Abstract
The high-affinity IgE receptor FcεRI is the mast cell (MC) receptor responsible for the involvement of MCs in IgE-associated allergic disorders. Activation of the FcεRI is achieved via crosslinking by multivalent antigen (Ag) recognized by IgE resulting in degranulation and proinflammatory cytokine production. In comparison to the T- and B-cell receptor complexes, for which several co-receptors orchestrating the initial signaling events have been described, information is scarce about FcεRI-associated proteins. Additionally, it is unclear how FcεRI signaling synergizes with input from other receptors and how regulators affect this synergistic response. We found that the HDL receptor SR-BI (gene name: Scarb1/SCARB1) is expressed in MCs, functionally associates with FcεRI, and regulates the plasma membrane cholesterol content in cholesterol-rich plasma membrane nanodomains. This impacted the activation of MCs upon co-stimulation of the FcεRI with receptors known to synergize with FcεRI signaling. Amongst them, we investigated the co-activation of the FcεRI with the receptor tyrosine kinase KIT, the IL-33 receptor, and GPCRs activated by adenosine or PGE2. Scarb1-deficient bone marrow-derived MCs showed reduced cytokine secretion upon co-stimulation conditions suggesting a role for plasma membrane-associated cholesterol regulating respective MC activation. Mimicking Scarb1 deficiency by cholesterol depletion employing MβCD, we identified PKB and PLCγ1 as cholesterol-sensitive proteins downstream of FcεRI activation in bone marrow-derived MCs. When MCs were co-stimulated with stem cell factor (SCF) and Ag, PLCγ1 activation was boosted, which could be mitigated by cholesterol depletion and SR-BI inhibition. Similarly, SR-BI inhibition attenuated the synergistic response to PGE2 and anti-IgE in the human ROSAKIT WT MC line, suggesting that SR-BI is a crucial regulator of synergistic MC activation.
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Affiliation(s)
- Sandro Capellmann
- Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Marlies Kauffmann
- Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Michel Arock
- Department of Hematological Biology, Pitié-Salpêtrière Charles-Foix Hospital, AP-HP Sorbonne University, Paris, France
| | - Michael Huber
- Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, Aachen, Germany
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2
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Au CW, Manfield I, Webb ME, Paci E, Turnbull WB, Ross JF. The Mutagenic Plasticity of the Cholera Toxin B-Subunit Surface Residues: Stability and Affinity. Toxins (Basel) 2024; 16:133. [PMID: 38535799 PMCID: PMC10974167 DOI: 10.3390/toxins16030133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 02/24/2024] [Accepted: 02/27/2024] [Indexed: 04/01/2024] Open
Abstract
Mastering selective molecule trafficking across human cell membranes poses a formidable challenge in healthcare biotechnology while offering the prospect of breakthroughs in drug delivery, gene therapy, and diagnostic imaging. The cholera toxin B-subunit (CTB) has the potential to be a useful cargo transporter for these applications. CTB is a robust protein that is amenable to reengineering for diverse applications; however, protein redesign has mostly focused on modifications of the N- and C-termini of the protein. Exploiting the full power of rational redesign requires a detailed understanding of the contributions of the surface residues to protein stability and binding activity. Here, we employed Rosetta-based computational saturation scans on 58 surface residues of CTB, including the GM1 binding site, to analyze both ligand-bound and ligand-free structures to decipher mutational effects on protein stability and GM1 affinity. Complimentary experimental results from differential scanning fluorimetry and isothermal titration calorimetry provided melting temperatures and GM1 binding affinities for 40 alanine mutants among these positions. The results showed that CTB can accommodate diverse mutations while maintaining its stability and ligand binding affinity. These mutations could potentially allow modification of the oligosaccharide binding specificity to change its cellular targeting, alter the B-subunit intracellular routing, or impact its shelf-life and in vivo half-life through changes to protein stability. We anticipate that the mutational space maps presented here will serve as a cornerstone for future CTB redesigns, paving the way for the development of innovative biotechnological tools.
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Affiliation(s)
- Cheuk W. Au
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Iain Manfield
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Michael E. Webb
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
- School of Chemistry, University of Leeds, Leeds LS2 9JT, UK
| | - Emanuele Paci
- Dipartimento di Fisica e Astronomia “Augusto Righi”, Viale Berti Pichat 6/2, 40127 Bologna, Italy
| | - W. Bruce Turnbull
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
- School of Chemistry, University of Leeds, Leeds LS2 9JT, UK
| | - James F. Ross
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
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3
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Das O, Masid A, Chakraborty M, Gope A, Dutta S, Bhaumik M. Butyrate driven raft disruption trots off enteric pathogen invasion: possible mechanism of colonization resistance. Gut Pathog 2023; 15:19. [PMID: 37085870 PMCID: PMC10122309 DOI: 10.1186/s13099-023-00545-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 04/09/2023] [Indexed: 04/23/2023] Open
Abstract
The gut microbiome derived short chain fatty acids perform multitude of functions to maintain gut homeostasis. Here we studied how butyrate stymie enteric bacterial invasion in cell using a simplistic binary model. The surface of the mammalian cells is enriched with microdomains rich in cholesterol that are known as rafts and act as entry points for pathogens. We showed that sodium butyrate treated RAW264.7 cells displayed reduced membrane cholesterol and less cholera-toxin B binding coupled with increased membrane fluidity compared to untreated cells indicating that reduced membrane cholesterol caused disruption of lipid rafts. The implication of such cellular biophysical changes on the invasion of enteric pathogenic bacteria was assessed. Our study showed, in comparison to untreated cells, butyrate-treated cells significantly reduced the invasion of Shigella and Salmonella, and these effects were found to be reversed by liposomal cholesterol treatment, increasing the likelihood that the rafts' function against bacterial invasion. The credence of ex vivo studies found to be in concordance in butyrate fed mouse model as evident from the significant drift towards a protective phenotype against virulent enteric pathogen invasion as compared to untreated mice. To produce a cytokine balance towards anti-inflammation, butyrate-treated mice produced more of the gut tissue anti-inflammatory cytokine IL-10 and less of the pro-inflammatory cytokines TNF-α, IL-6, and IFN-γ. In histological studies of Shigella infected gut revealed a startling observation where number of neutrophils infiltration was noted which was correlated with the pathology and was essentially reversed by butyrate treatment. Our results ratchet up a new dimension of our understanding how butyrate imparts resistance to pathogen invasion in the gut.
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Affiliation(s)
- Oishika Das
- ICMR-National Institute of Cholera and Enteric Diseases, P-33 C.I. T Road, Beleghata, Kolkata, West Bengal, 700010, India
| | - Aaheli Masid
- ICMR-National Institute of Cholera and Enteric Diseases, P-33 C.I. T Road, Beleghata, Kolkata, West Bengal, 700010, India
| | - Mainak Chakraborty
- ICMR-National Institute of Cholera and Enteric Diseases, P-33 C.I. T Road, Beleghata, Kolkata, West Bengal, 700010, India
| | - Animesh Gope
- ICMR-National Institute of Cholera and Enteric Diseases, P-33 C.I. T Road, Beleghata, Kolkata, West Bengal, 700010, India
| | - Shanta Dutta
- ICMR-National Institute of Cholera and Enteric Diseases, P-33 C.I. T Road, Beleghata, Kolkata, West Bengal, 700010, India
| | - Moumita Bhaumik
- ICMR-National Institute of Cholera and Enteric Diseases, P-33 C.I. T Road, Beleghata, Kolkata, West Bengal, 700010, India.
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4
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Greene M, Hernandez-Corbacho MJ, Ostermeyer-Fay AG, Hannun YA, Canals D. A simple, highly sensitive, and facile method to quantify ceramide at the plasma membrane. J Lipid Res 2023; 64:100322. [PMID: 36549592 PMCID: PMC9853358 DOI: 10.1016/j.jlr.2022.100322] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/12/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
The role of ceramide in biological functions is typically based on the elevation of cellular ceramide, measured by LC-MS in the total cell lysate. However, it has become increasingly appreciated that ceramide in different subcellular organelles regulates specific functions. In the plasma membrane, changes in ceramide levels might represent a small percentage of the total cellular ceramide, evading MS detection but playing a critical role in cell signaling. Importantly, there are currently no efficient techniques to quantify ceramide in the plasma membrane. Here, we developed a method to measure the mass of ceramide in the plasma membrane using a short protocol that is based on the hydrolysis of plasma membrane ceramide into sphingosine by the action of exogenously applied bacterial recombinant neutral ceramidase. Plasma membrane ceramide content can then be determined by measuring the newly generated sphingosine at a stoichiometry of 1:1. A key step of this protocol is the chemical fixation of cells to block cellular sphingolipid metabolism, especially of sphingosine to sphingosine 1-phosphate. We confirmed that chemical fixation does not disrupt the lipid composition at the plasma membrane, which remains intact during the time of the assay. We illustrate the power of the approach by applying this protocol to interrogate the effects of the chemotherapeutic compound doxorubicin. Here we distinguished two pools of ceramide, depending on the doxorubicin concentration, consolidating different reports. In summary, we have developed the first approach to quantify ceramide in the plasma membrane, allowing the study of new avenues in sphingolipid compartmentalization and function.
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Affiliation(s)
- Meaghan Greene
- Department of Medicine, Stony Brook University, Stony Brook, NY, USA
| | | | | | - Yusuf A Hannun
- Department of Medicine, Stony Brook University, Stony Brook, NY, USA; Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, USA; Department of Biochemistry, Stony Brook University, Stony Brook, NY, USA
| | - Daniel Canals
- Department of Medicine, Stony Brook University, Stony Brook, NY, USA; Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, USA.
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5
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Sofińska K, Lupa D, Chachaj-Brekiesz A, Czaja M, Kobierski J, Seweryn S, Skirlińska-Nosek K, Szymonski M, Wilkosz N, Wnętrzak A, Lipiec E. Revealing local molecular distribution, orientation, phase separation, and formation of domains in artificial lipid layers: Towards comprehensive characterization of biological membranes. Adv Colloid Interface Sci 2022; 301:102614. [PMID: 35190313 DOI: 10.1016/j.cis.2022.102614] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/28/2022] [Accepted: 02/01/2022] [Indexed: 01/01/2023]
Abstract
Lipids, together with molecules such as DNA and proteins, are one of the most relevant systems responsible for the existence of life. Selected lipids are able to assembly into various organized structures, such as lipid membranes. The unique properties of lipid membranes determine their complex functions, not only to separate biological environments, but also to participate in regulatory functions, absorption of nutrients, cell-cell communication, endocytosis, cell signaling, and many others. Despite numerous scientific efforts, still little is known about the reason underlying the variability within lipid membranes, and its biochemical significance. In this review, we discuss the structural complexity of lipid membranes, as well as the importance to simplify studied systems in order to understand phenomena occurring in natural, complex membranes. Such systems require a model interface to be analyzed. Therefore, here we focused on analytical studies of artificial systems at various interfaces. The molecular structure of lipid membranes, specifically the nanometric thickens of molecular bilayer, limits in a major extent the choice of highly sensitive methods suitable to study such structures. Therefore, we focused on methods that combine high sensitivity, and/or chemical selectivity, and/or nanometric spatial resolution, such as atomic force microscopy, nanospectroscopy (tip-enhanced Raman spectroscopy, infrared nanospectroscopy), phase modulation infrared reflection-absorption spectroscopy, sum-frequency generation spectroscopy. We summarized experimental and theoretical approaches providing information about molecular structure and composition, lipid spatial distribution (phase separation), organization (domain shape, molecular orientation) of lipid membranes, and real-time visualization of the influence of various molecules (proteins, drugs) on their integrity. An integral part of this review discusses the latest achievements in the field of lipid layer-based biosensors.
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6
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Ren LL, Zhou JY, Liang SJ, Wang XQ. Impaired intestinal stem cell activity in ETEC infection: enterotoxins, cyclic nucleotides, and Wnt signaling. Arch Toxicol 2022; 96:1213-1225. [PMID: 35226135 DOI: 10.1007/s00204-021-03213-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 12/21/2021] [Indexed: 12/25/2022]
Abstract
Enterotoxigenic Escherichia coli (ETEC) in humans and animals colonizes the intestine and thereafter secrets heat-stable enterotoxin (ST) with or without heat-labile enterotoxin (LT), which triggers massive fluid and electrolyte secretion into the gut lumen. The crosstalk between the cyclic nucleotide-dependent protein kinase/cystic fibrosis transmembrane conductance regulator (cAMP or cGMP/CFTR) pathway involved in ETEC-induced diarrhea channels, and the canonical Wnt/β-catenin signaling pathway leads to changes in intestinal stem cell (ISC) fates, which are strongly associated with developmental disorders caused by diarrhea. We review how alterations in enterotoxin-activated ion channel pathways and the canonical Wnt/β-catenin signaling pathway can explain inhibited intestinal epithelial activity, characterize alterations in the crosstalk of cyclic nucleotides, and predict harmful effects on ISCs in targeted therapy. Besides, we discuss current deficits in the understanding of enterotoxin-intestinal epithelial cell activity relationships that should be considered when interpreting sequelae of diarrhea.
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Affiliation(s)
- Lu-Lu Ren
- College of Animal Science, South China Agricultural University/Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Animal Nutrition Control/National Engineering Research Center for Breeding Swine Industry, Guangzhou, 510642, China
| | - Jia-Yi Zhou
- College of Animal Science, South China Agricultural University/Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Animal Nutrition Control/National Engineering Research Center for Breeding Swine Industry, Guangzhou, 510642, China
| | - Shao-Jie Liang
- College of Animal Science, South China Agricultural University/Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Animal Nutrition Control/National Engineering Research Center for Breeding Swine Industry, Guangzhou, 510642, China
| | - Xiu-Qi Wang
- College of Animal Science, South China Agricultural University/Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Animal Nutrition Control/National Engineering Research Center for Breeding Swine Industry, Guangzhou, 510642, China.
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7
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8
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Balmforth MR, Haigh J, Kumar V, Dai W, Tiede C, Tomlinson DC, Deuchars J, Webb ME, Turnbull WB. Piggybacking on the Cholera Toxin: Identification of a CTB-Binding Protein as an Approach for Targeted Delivery of Proteins to Motor Neurons. Bioconjug Chem 2021; 32:2205-2212. [PMID: 34565149 DOI: 10.1021/acs.bioconjchem.1c00373] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A significant unmet need exists for the delivery of biologic drugs such as polypeptides or nucleic acids to the central nervous system for the treatment and understanding of neurodegenerative diseases. Naturally occurring bacterial toxins have been considered as tools to meet this need. However, due to the complexity of tethering macromolecular drugs to toxins and the inherent dangers of working with large quantities of recombinant toxins, no such route has been successfully exploited. Developing a method where a bacterial toxin's nontoxic targeting subunit can be assembled with a drug immediately prior to in vivo administration has the potential to circumvent some of these issues. Using a phage-display screen, we identified two antibody mimetics, anticholera toxin Affimer (ACTA)-A2 and ACTA-C6 that noncovalently associate with the nonbinding face of the cholera toxin B-subunit. In a first step toward the development of a nonviral motor neuron drug-delivery vehicle, we show that Affimers can be selectively delivered to motor neurons in vivo.
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Affiliation(s)
- Matthew R Balmforth
- School of Chemistry, School of Biomedical Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, U.K
| | - Jessica Haigh
- School of Chemistry, School of Biomedical Sciences and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, U.K
| | - Vajinder Kumar
- School of Chemistry and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, U.K.,Akal University, Talwandi Sabo, Punjab 151302, India
| | - Wenyue Dai
- School of Chemistry and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, U.K
| | - Christian Tiede
- School of Molecular and Cellular Biology, and Astbury Centre for Structural and Molecular Biology, University of Leeds, Faculty of Biological Sciences, Leeds LS2 9JT, U.K
| | - Darren C Tomlinson
- School of Molecular and Cellular Biology, and Astbury Centre for Structural and Molecular Biology, University of Leeds, Faculty of Biological Sciences, Leeds LS2 9JT, U.K
| | - Jim Deuchars
- School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, U.K
| | - Michael E Webb
- School of Chemistry and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, U.K
| | - W Bruce Turnbull
- School of Chemistry and Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, U.K
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9
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Santos-Martin C, Wang G, Subedi P, Hor L, Totsika M, Paxman JJ, Heras B. Structural bioinformatic analysis of DsbA proteins and their pathogenicity associated substrates. Comput Struct Biotechnol J 2021; 19:4725-4737. [PMID: 34504665 PMCID: PMC8405906 DOI: 10.1016/j.csbj.2021.08.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 08/12/2021] [Accepted: 08/12/2021] [Indexed: 01/02/2023] Open
Abstract
The disulfide bond (DSB) forming system and in particular DsbA, is a key bacterial oxidative folding catalyst. Due to its role in promoting the correct assembly of a wide range of virulence factors required at different stages of the infection process, DsbA is a master virulence rheostat, making it an attractive target for the development of new virulence blockers. Although DSB systems have been extensively studied across different bacterial species, to date, little is known about how DsbA oxidoreductases are able to recognize and interact with such a wide range of substrates. This review summarizes the current knowledge on the DsbA enzymes, with special attention on their interaction with the partner oxidase DsbB and substrates associated with bacterial virulence. The structurally and functionally diverse set of bacterial proteins that rely on DsbA-mediated disulfide bond formation are summarized. Local sequence and secondary structure elements of these substrates are analyzed to identify common elements recognized by DsbA enzymes. This not only provides information on protein folding systems in bacteria but also offers tools for identifying new DsbA substrates and informs current efforts aimed at developing DsbA targeted anti-microbials.
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Affiliation(s)
- Carlos Santos-Martin
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Australia
| | - Geqing Wang
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Australia
| | - Pramod Subedi
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Australia
| | - Lilian Hor
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Australia
| | - Makrina Totsika
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Queensland University of Technology, Brisbane, Australia
| | - Jason John Paxman
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Australia
| | - Begoña Heras
- Department of Biochemistry and Genetics, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Australia
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10
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Su F, Wu Y, Li J, Huang Y, Yu B, Xu L, Xue Y, Xiao C, Yuan X. Escherichia coli Heat-Labile Enterotoxin B Subunit Combined with Ginsenoside Rg1 as an Intranasal Adjuvant Triggers Type I Interferon Signaling Pathway and Enhances Adaptive Immune Responses to an Inactivated PRRSV Vaccine in ICR Mice. Vaccines (Basel) 2021; 9:vaccines9030266. [PMID: 33809809 PMCID: PMC8002527 DOI: 10.3390/vaccines9030266] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/12/2021] [Accepted: 03/14/2021] [Indexed: 12/20/2022] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) is a major pathogen that has threatened the global swine industry for almost 30 years. Because current vaccines do not provide complete protection, exploration of new preventive strategies is urgently needed. Here, we combined a heat-labile enterotoxin B subunit of Escherichia coli (LTB) and ginsenoside Rg1 to form an intranasal adjuvant and evaluated its enhancement of immune responses in mice when added to an inactivated-PRRSV vaccine. The combination adjuvant synergistically elicited higher neutralizing and non-neutralizing (immunoglobulin G and A) antibody responses in the circulatory system and respiratory tract, and enhanced T and B lymphocyte proliferation, CD4+ T-cell priming, and cytotoxic CD4+ T cell activities in mononuclear cells from spleen and lung tissues when compared to the PRRSV vaccine alone, and it resulted in balanced Th1/Th2/Th17 responses. More importantly, we observed that the combination adjuvant also up-regulated type I interferon signaling, which may contribute to improvement in adaptive immune responses. These results highlight the potential value of a combined adjuvant approach for improving the efficacy of vaccination against PRRSV. Further study is required to evaluate the efficacy of this combined adjuvant in swine.
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Affiliation(s)
- Fei Su
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310002, China; (F.S.); (Y.W.); (J.L.); (Y.H.); (B.Y.); (L.X.); (C.X.)
| | - Yige Wu
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310002, China; (F.S.); (Y.W.); (J.L.); (Y.H.); (B.Y.); (L.X.); (C.X.)
| | - Junxing Li
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310002, China; (F.S.); (Y.W.); (J.L.); (Y.H.); (B.Y.); (L.X.); (C.X.)
| | - Yee Huang
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310002, China; (F.S.); (Y.W.); (J.L.); (Y.H.); (B.Y.); (L.X.); (C.X.)
| | - Bin Yu
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310002, China; (F.S.); (Y.W.); (J.L.); (Y.H.); (B.Y.); (L.X.); (C.X.)
| | - Lihua Xu
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310002, China; (F.S.); (Y.W.); (J.L.); (Y.H.); (B.Y.); (L.X.); (C.X.)
| | - Yin Xue
- Zhejiang Center of Animal Disease Control, Hangzhou 310020, China;
| | - Chenwen Xiao
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310002, China; (F.S.); (Y.W.); (J.L.); (Y.H.); (B.Y.); (L.X.); (C.X.)
| | - Xiufang Yuan
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310002, China; (F.S.); (Y.W.); (J.L.); (Y.H.); (B.Y.); (L.X.); (C.X.)
- Correspondence:
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11
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Asico LD, Rozyyev S, Crusan AM, Jose PA, Villar VAM. Elucidating the Role of Lipid Rafts on G Protein-Coupled Receptor Function in the Mouse Kidney: An In Vivo Approach. Methods Mol Biol 2021; 2187:187-206. [PMID: 32770507 DOI: 10.1007/978-1-0716-0814-2_10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Numerous G protein-coupled receptors (GPCRs) and GPCR-signaling molecules reside in lipid rafts and thus, are inherently regulated in these microdomains. However, the limitations of current methods to investigate lipid raft biology and GPCR activity in situ have hindered the complete understanding of the molecular underpinnings of GPCR trafficking and signaling, especially in the whole organism. This book chapter details an innovative in vivo approach to study the crucial role of lipid rafts on the workings of GPCRs in the mouse kidney. This protocol involves the use of a modified mini osmotic pump to deliver an agent that selectively disrupts the lipid raft in the kidney.
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Affiliation(s)
- Laureano D Asico
- Division of Renal Diseases and Hypertension, School of Medicine and Health Sciences, The George Washington University, Washington, DC, USA.
| | - Selim Rozyyev
- Division of Renal Diseases and Hypertension, School of Medicine and Health Sciences, The George Washington University, Washington, DC, USA.,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, DC, USA
| | - Annabelle M Crusan
- Research Animal Facility, The Children's Research Institute, Children's National Health System, Washington, DC, USA
| | - Pedro A Jose
- Division of Renal Diseases and Hypertension, School of Medicine and Health Sciences, The George Washington University, Washington, DC, USA
| | - Van Anthony M Villar
- Division of Renal Diseases and Hypertension, School of Medicine and Health Sciences, The George Washington University, Washington, DC, USA.
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12
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Verma A, Zhu P, Xu K, Du T, Liao S, Liang Z, Raizada MK, Li Q. Angiotensin-(1-7) Expressed From Lactobacillus Bacteria Protect Diabetic Retina in Mice. Transl Vis Sci Technol 2020; 9:20. [PMID: 33344064 PMCID: PMC7735952 DOI: 10.1167/tvst.9.13.20] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 11/03/2020] [Indexed: 01/04/2023] Open
Abstract
Purpose A multitude of animal studies substantiates the beneficial effects of Ang-(1–7), a peptide hormone in the protective axis of the renin angiotensin system, in diabetes and its associated complications including diabetic retinopathy (DR). However, the clinical application of Ang-(1–7) is limited due to unfavorable pharmacological properties. As emerging evidence implicates gut dysbiosis in pathogenesis of diabetes and supports beneficial effects of probiotics, we sought to develop probiotics-based expression and delivery system to enhance Ang-(1–7) and evaluate the efficacy of engineered probiotics expressing Ang-(1–7) in attenuation of DR in animal models. Methods Ang-(1–7) was expressed in the Lactobacillus species as a secreted fusion protein with a trans-epithelial carrier to allow uptake into circulation. To evaluate the effects of Ang-(1–7) expressed from Lactobacillus paracasei (LP), adult diabetic eNOS−/− and Akita mice were orally gavaged with either 1 × 109 CFU of LP secreting Ang-(1–7) (LP-A), LP alone or vehicle, 3 times/week, for 8 and 12 weeks, respectively. Results Ang-(1–7) is efficiently expressed from different Lactobacillus species and secreted into circulation in mice fed with LP-A. Oral administration of LP-A significantly reduced diabetes-induced loss of retinal vascular capillaries. LP-A treatment also prevented loss of retinal ganglion cells, and significantly decreased retinal inflammatory cytokine expression in both diabetic eNOS−/− and Akita mice. Conclusions These results provide proof-of-concept for feasibility and efficacy of using engineered probiotic species as live vector for delivery of Ang-(1–7) with enhanced bioavailability. Translational Relevance Probiotics-based delivery of Ang-(1–7) may hold important therapeutic potential for the treatment of DR and other diabetic complications.
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Affiliation(s)
- Amrisha Verma
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Ping Zhu
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Kang Xu
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Tao Du
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Shengquan Liao
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Zhibing Liang
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Mohan K Raizada
- Physiology & Functional Genomics, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Qiuhong Li
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
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13
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Cooper-Knock J, Zhang S, Kenna KP, Moll T, Franklin JP, Allen S, Nezhad HG, Iacoangeli A, Yacovzada NY, Eitan C, Hornstein E, Elhaik E, Celadova P, Bose D, Farhan S, Fishilevich S, Lancet D, Morrison KE, Shaw CE, Al-Chalabi A, Veldink JH, Kirby J, Snyder MP, Shaw PJ. Rare Variant Burden Analysis within Enhancers Identifies CAV1 as an ALS Risk Gene. Cell Rep 2020; 33:108456. [PMID: 33264630 PMCID: PMC7710676 DOI: 10.1016/j.celrep.2020.108456] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 09/15/2020] [Accepted: 11/09/2020] [Indexed: 02/01/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease. CAV1 and CAV2 organize membrane lipid rafts (MLRs) important for cell signaling and neuronal survival, and overexpression of CAV1 ameliorates ALS phenotypes in vivo. Genome-wide association studies localize a large proportion of ALS risk variants within the non-coding genome, but further characterization has been limited by lack of appropriate tools. By designing and applying a pipeline to identify pathogenic genetic variation within enhancer elements responsible for regulating gene expression, we identify disease-associated variation within CAV1/CAV2 enhancers, which replicate in an independent cohort. Discovered enhancer mutations reduce CAV1/CAV2 expression and disrupt MLRs in patient-derived cells, and CRISPR-Cas9 perturbation proximate to a patient mutation is sufficient to reduce CAV1/CAV2 expression in neurons. Additional enrichment of ALS-associated mutations within CAV1 exons positions CAV1 as an ALS risk gene. We propose CAV1/CAV2 overexpression as a personalized medicine target for ALS.
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Affiliation(s)
- Johnathan Cooper-Knock
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK.
| | - Sai Zhang
- Stanford Center for Genomics and Personalized Medicine, Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kevin P Kenna
- Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Tobias Moll
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - John P Franklin
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Samantha Allen
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Helia Ghahremani Nezhad
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Alfredo Iacoangeli
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Nancy Y Yacovzada
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Chen Eitan
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Eran Hornstein
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Eran Elhaik
- Department of Biology, Lund University, Lund, Sweden
| | - Petra Celadova
- Sheffield Institute for Nucleic Acids, University of Sheffield, Sheffield, UK
| | - Daniel Bose
- Sheffield Institute for Nucleic Acids, University of Sheffield, Sheffield, UK
| | - Sali Farhan
- Analytic and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Simon Fishilevich
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Doron Lancet
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | | | - Christopher E Shaw
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Ammar Al-Chalabi
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Jan H Veldink
- Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Janine Kirby
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Michael P Snyder
- Stanford Center for Genomics and Personalized Medicine, Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Pamela J Shaw
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK.
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14
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Miller MC, Nesmelova IV, Daragan VA, Ippel H, Michalak M, Dregni A, Kaltner H, Kopitz J, Gabius HJ, Mayo KH. Pro4 prolyl peptide bond isomerization in human galectin-7 modulates the monomer-dimer equilibrum to affect function. Biochem J 2020; 477:3147-3165. [PMID: 32766716 PMCID: PMC7473712 DOI: 10.1042/bcj20200499] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 08/03/2020] [Accepted: 08/06/2020] [Indexed: 02/06/2023]
Abstract
Human galectin-7 (Gal-7; also termed p53-induced gene 1 product) is a multifunctional effector by productive pairing with distinct glycoconjugates and protein counter-receptors in the cytoplasm and nucleus, as well as on the cell surface. Its structural analysis by NMR spectroscopy detected doubling of a set of particular resonances, an indicator of Gal-7 existing in two conformational states in slow exchange on the chemical shift time scale. Structural positioning of this set of amino acids around the P4 residue and loss of this phenomenon in the bioactive P4L mutant indicated cis-trans isomerization at this site. Respective resonance assignments confirmed our proposal of two Gal-7 conformers. Mapping hydrogen bonds and considering van der Waals interactions in molecular dynamics simulations revealed a structural difference for the N-terminal peptide, with the trans-state being more exposed to solvent and more mobile than the cis-state. Affinity for lactose or glycan-inhibitable neuroblastoma cell surface contact formation was not affected, because both conformers associated with an overall increase in order parameters (S2). At low µM concentrations, homodimer dissociation is more favored for the cis-state of the protein than its trans-state. These findings give direction to mapping binding sites for protein counter-receptors of Gal-7, such as Bcl-2, JNK1, p53 or Smad3, and to run functional assays at low concentration to test the hypothesis that this isomerization process provides a (patho)physiologically important molecular switch for Gal-7.
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Affiliation(s)
- Michelle C. Miller
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455 U.S.A
| | - Irina V. Nesmelova
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455 U.S.A
| | - Vladimir A. Daragan
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455 U.S.A
| | - Hans Ippel
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455 U.S.A
- Department of Biochemistry, CARIM, University of Maastricht, Maastricht, The Netherlands
| | - Malwina Michalak
- Department of Applied Tumor Biology, Institute of Pathology, Medical School of the Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | - Aurelio Dregni
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455 U.S.A
| | - Herbert Kaltner
- Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-Maximillians-University Munich, Munich, Germany
| | - Jürgen Kopitz
- Department of Applied Tumor Biology, Institute of Pathology, Medical School of the Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | - Hans-Joachim Gabius
- Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-Maximillians-University Munich, Munich, Germany
| | - Kevin H. Mayo
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455 U.S.A
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15
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Verma A, Xu K, Du T, Zhu P, Liang Z, Liao S, Zhang J, Raizada MK, Grant MB, Li Q. Erratum: Expression of Human ACE2 in Lactobacillus and Beneficial Effects in Diabetic Retinopathy in Mice. Mol Ther Methods Clin Dev 2020; 17:400. [PMID: 32128344 DOI: 10.1016/j.omtm.2020.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
[This corrects the article DOI: 10.1016/j.omtm.2019.06.007.].
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16
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Duan Q, Xia P, Nandre R, Zhang W, Zhu G. Review of Newly Identified Functions Associated With the Heat-Labile Toxin of Enterotoxigenic Escherichia coli. Front Cell Infect Microbiol 2019; 9:292. [PMID: 31456954 PMCID: PMC6700299 DOI: 10.3389/fcimb.2019.00292] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 07/29/2019] [Indexed: 12/11/2022] Open
Abstract
Heat-labile toxin (LT) is a well-characterized powerful enterotoxin produced by enterotoxigenic Escherichia coli (ETEC). This toxin is known to contribute to diarrhea in young children in developing countries, international travelers, as well as many different species of young animals. Interestingly, it has also been revealed that LT is involved in other activities in addition to its role in enterotoxicity. Recent studies have indicated that LT toxin enhances enteric pathogen adherence and subsequent intestinal colonization. LT has also been shown to act as a powerful adjuvant capable of upregulating vaccine antigenicity; it also serves as a protein or antigenic peptide display platform for new vaccine development, and can be used as a naturally derived cell targeting and protein delivery tool. This review summarizes the epidemiology, secretion, delivery, and mechanisms of action of LT, while also highlighting new functions revealed by recent studies.
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Affiliation(s)
- Qiangde Duan
- College of Veterinary Medicine, Institute of Comparative Medicine, Yangzhou University, Yangzhou, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Pengpeng Xia
- College of Veterinary Medicine, Institute of Comparative Medicine, Yangzhou University, Yangzhou, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Rahul Nandre
- Department of Microbiology and Immunology, Uniformed Services University, Bethesda, MD, United States
| | - Weiping Zhang
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Guoqiang Zhu
- College of Veterinary Medicine, Institute of Comparative Medicine, Yangzhou University, Yangzhou, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
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17
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Verma A, Xu K, Du T, Zhu P, Liang Z, Liao S, Zhang J, Raizada MK, Grant MB, Li Q. Expression of Human ACE2 in Lactobacillus and Beneficial Effects in Diabetic Retinopathy in Mice. Mol Ther Methods Clin Dev 2019; 14:161-170. [PMID: 31380462 PMCID: PMC6661465 DOI: 10.1016/j.omtm.2019.06.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 06/25/2019] [Indexed: 02/06/2023]
Abstract
The angiotensin converting enzyme 2 (ACE2) catalyzes the degradation of Angiotensin II (Ang II) to generate Angiotensin-(1-7), which reduces inflammation and oxidative stress stimulated by Ang II. ACE2 has been shown to be protective in cardiovascular and metabolic diseases including diabetes and its complications. However, the challenge for its clinical application is large-scale production of high-quality ACE2 with sufficient target tissue bioavailability. We developed an expression and delivery system based on the use of probiotic species Lactobacillus paracasei (LP) to serve as a live vector for oral delivery of human ACE2. We show that codon-optimized ACE2 can be efficiently expressed in LP. Mice treated with the recombinant LP expressing the secreted ACE2 in fusion with the non-toxic subunit B of cholera toxin, which acts as a carrier to facilitate transmucosal transport, showed increased ACE2 activities in serum and tissues. ACE2-LP administration reduced the number of acellular capillaries, blocked retinal ganglion cell loss, and decreased retinal inflammatory cytokine expression in two mouse models of diabetic retinopathy. These results provide proof of concept for feasibility of using engineered probiotic species as live vector for delivery of human ACE2 with enhanced tissue bioavailability for treating diabetic retinopathy, as well as other diabetic complications.
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Affiliation(s)
- Amrisha Verma
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610-0284, USA
| | - Kang Xu
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610-0284, USA
| | - Tao Du
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610-0284, USA
| | - Ping Zhu
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610-0284, USA
| | - Zhibing Liang
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610-0284, USA
| | - Shengquan Liao
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610-0284, USA
| | - Juantao Zhang
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610-0284, USA
| | - Mohan K Raizada
- Department of Physiology & Functional Genomics, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Maria B Grant
- Department of Ophthalmology & Visual Sciences, University of Alabama, Birmingham, AL 35294, USA
| | - Qiuhong Li
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610-0284, USA
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18
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Kim BM, Kang TJ. Expression of B subunit of E. coli heat-labile enterotoxin in the progenies of transgenic tobacco bred by crossing nuclear- and chloroplast-transgenic lines. Protein Expr Purif 2019; 155:54-58. [PMID: 30468854 DOI: 10.1016/j.pep.2018.11.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 10/18/2018] [Accepted: 11/15/2018] [Indexed: 01/26/2023]
Abstract
The B subunit of Escherichia coli heat-labile toxin (LTB) is a model antigen that induces a strong immune response upon oral administration and enhances immune responses to conjugated and co-administered antigens. We previously examined high expression levels of LTB in plants by chloroplast and synthetic LTB gene expression and found substantially higher expression levels of LTB, compared to nuclear LTB expression in wild-type plants. The 2.5% LTB protein of total soluble protein that was observed by chloroplast transformation was approximately 250-fold greater expression than that of LTB via nuclear genome integration. In addition, the amount of LTB protein found in transgenic tobacco leaves using a synthetic LTB gene was 2.2% of the total soluble plant protein, which was approximately 200-fold higher than that in plants with native LTB gene expression. The purpose of our experiment was to increase LTB levels in plants by crossing chloroplast-transformed and synthetic LTB transgenic lines produced previously to express higher LTB levels. LTB protein levels in the F1 transgenic tobacco plants was significantly higher (3.3%), compared to the 2.2% of chloroplast-transformed line or 2.8% of synthetic LTB gene line. Our results suggest that LTB expression was successfully enhanced in the F1 hybrid generation of transgenic tobacco plants.
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Affiliation(s)
- Bo-Mi Kim
- Department of Chemical Engineering, Wonkwang University, Iksan, 54538, South Korea
| | - Tae-Jin Kang
- Division of Biological Sciences, Wonkwang University, Iksan, 54538, South Korea.
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Mahon CS, Wildsmith GC, Haksar D, de Poel E, Beekman JM, Pieters RJ, Webb ME, Turnbull WB. A ‘catch-and-release’ receptor for the cholera toxin. Faraday Discuss 2019; 219:112-127. [DOI: 10.1039/c9fd00017h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thermoresponsive receptors for the recognition unit of the cholera toxin (CTB) can recognise the protein with nanomolar affinity. An increase in temperature can drastically reduce their avidity, enabling on-demand release of CTB.
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Affiliation(s)
- Clare S. Mahon
- School of Chemistry and Astbury Centre for Structural Molecular Biology
- University of Leeds
- Leeds
- UK
- Department of Chemistry
| | - Gemma C. Wildsmith
- School of Chemistry and Astbury Centre for Structural Molecular Biology
- University of Leeds
- Leeds
- UK
| | - Diksha Haksar
- Department of Chemical Biology & Drug Discovery
- Utrecht Institute for Pharmaceutical Sciences
- Utrecht University
- Utrecht
- The Netherlands
| | - Eyleen de Poel
- Department of Pediatric Pulmonology
- Wilhelmina Children’s Hospital and Regenerative Medicine Center Utrecht
- University Medical Centre Utrecht
- Utrecht
- The Netherlands
| | - Jeffrey M. Beekman
- Department of Pediatric Pulmonology
- Wilhelmina Children’s Hospital and Regenerative Medicine Center Utrecht
- University Medical Centre Utrecht
- Utrecht
- The Netherlands
| | - Roland J. Pieters
- Department of Chemical Biology & Drug Discovery
- Utrecht Institute for Pharmaceutical Sciences
- Utrecht University
- Utrecht
- The Netherlands
| | - Michael E. Webb
- School of Chemistry and Astbury Centre for Structural Molecular Biology
- University of Leeds
- Leeds
- UK
| | - W. Bruce Turnbull
- School of Chemistry and Astbury Centre for Structural Molecular Biology
- University of Leeds
- Leeds
- UK
- Department of Chemistry
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20
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Coria LM, Risso GS, Guaimas FF, Ferrero MC, Bruno L, Pasquevich KA, Cassataro J. Oral co-administration of a bacterial protease inhibitor in the vaccine formulation increases antigen delivery at the intestinal epithelial barrier. J Control Release 2019; 293:158-71. [PMID: 30496771 DOI: 10.1016/j.jconrel.2018.11.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/19/2018] [Accepted: 11/26/2018] [Indexed: 01/18/2023]
Abstract
The study of capture and processing of antigens (Ags) by intestinal epithelial cells is very important for development of new oral administration systems. Efficient oral Ag delivery systems must resist enzymatic degradation by gastric and intestinal proteases and deliver the Ag across biological barriers. The recombinant unlipidated outer membrane protein from Brucella spp. (U-Omp19) is a protease inhibitor with immunostimulatory properties used as adjuvant in oral vaccine formulations. In the present work we further characterized its mechanism of action and studied the interaction and effect of U-Omp19 on the intestinal epithelium. We found that U-Omp19 inhibited protease activity from murine intestinal brush-border membranes and cysteine proteases from human intestinal epithelial cells (IECs) promoting co-administered Ag accumulation within lysosomal compartments of IECs. In addition, we have shown that co-administration of U-Omp19 facilitated the transcellular passage of Ag through epithelial cell monolayers in vitro and in vivo while did not affect epithelial cell barrier permeability. Finally, oral co-delivery of U-Omp19 in mice induced the production of Ag-specific IgA in feces and the increment of CD103+ CD11b− CD8α+ dendritic cells subset at Peyer's patches. Taken together, these data describe a new mechanism of action of a mucosal adjuvant and support the use of this rationale/strategy in new oral delivery systems for vaccines. The bacterial protease inhibitor U-Omp19 limits antigens proteolysis by enterocytes. Oral co-administration of U-Omp19 increases antigen half-life inside enterocytes. U-Omp19 oral administration does not affect epithelial cell barrier permeability. Oral co-delivery of U-Omp19 increases frequency of dendritic cells bearing antigen. U-Omp19 increases the half-life and immunogenicity of cholera toxin subunit B antigen.
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21
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Lavinsky F, Wollstein G, Tauber J, Schuman JS. The Future of Imaging in Detecting Glaucoma Progression. Ophthalmology 2017; 124:S76-S82. [PMID: 29157365 DOI: 10.1016/j.ophtha.2017.10.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 09/11/2017] [Accepted: 10/05/2017] [Indexed: 12/12/2022] Open
Abstract
Ocular imaging has been heavily incorporated into glaucoma management and provides important information that aids in the detection of disease progression. Longitudinal studies have shown that the circumpapillary retinal nerve fiber layer is an important parameter for glaucoma progression detection, whereas other studies have demonstrated that macular parameters, such as the ganglion cell inner plexiform layer and optic nerve head parameters, also are useful for progression detection. The introduction of novel technologies with faster scan speeds, wider scanning fields, higher resolution, and improved tissue penetration has enabled the precise quantification of additional key ocular structures, such as the individual retinal layers, optic nerve head, choroid, and lamina cribrosa. Furthermore, extracting functional information from scans such as blood flow rate and oxygen consumption provides new perspectives on the disease and its progression. These novel methods promise improved detection of glaucoma progression and better insight into the mechanisms of progression that will lead to better targeted treatment options to prevent visual damage and blindness.
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Affiliation(s)
- Fabio Lavinsky
- NYU Langone Eye Center, New York University School of Medicine, New York, New York
| | - Gadi Wollstein
- NYU Langone Eye Center, New York University School of Medicine, New York, New York
| | - Jenna Tauber
- NYU Langone Eye Center, New York University School of Medicine, New York, New York
| | - Joel S Schuman
- NYU Langone Eye Center, New York University School of Medicine, New York, New York.
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22
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Royal JM, Matoba N. Therapeutic Potential of Cholera Toxin B Subunit for the Treatment of Inflammatory Diseases of the Mucosa. Toxins (Basel) 2017; 9:toxins9120379. [PMID: 29168738 PMCID: PMC5744099 DOI: 10.3390/toxins9120379] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/14/2017] [Accepted: 11/21/2017] [Indexed: 01/03/2023] Open
Abstract
Cholera toxin B subunit (CTB) is a mucosal immunomodulatory protein that induces robust mucosal and systemic antibody responses. This well-known biological activity has been exploited in cholera prevention (as a component of Dukoral® vaccine) and vaccine development for decades. On the other hand, several studies have investigated CTB's immunotherapeutic potential in the treatment of inflammatory diseases such as Crohn's disease and asthma. Furthermore, we recently found that a variant of CTB could induce colon epithelial wound healing in mouse colitis models. This review summarizes the possible mechanisms behind CTB's anti-inflammatory activity and discuss how the protein could impact mucosal inflammatory disease treatment.
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Affiliation(s)
- Joshua M Royal
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202, USA.
- Center for Predictive Medicine, University of Louisville, Louisville, KY 40202, USA.
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA.
| | - Nobuyuki Matoba
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202, USA.
- Center for Predictive Medicine, University of Louisville, Louisville, KY 40202, USA.
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA.
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Tanaka A, Tumkosit U, Nakamura S, Motooka D, Kishishita N, Priengprom T, Sa-Ngasang A, Kinoshita T, Takeda N, Maeda Y. Genome-Wide Screening Uncovers the Significance of N-Sulfation of Heparan Sulfate as a Host Cell Factor for Chikungunya Virus Infection. J Virol 2017; 91:e00432-17. [PMID: 28404855 DOI: 10.1128/JVI.00432-17] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 04/03/2017] [Indexed: 02/07/2023] Open
Abstract
The molecular mechanisms underlying chikungunya virus (CHIKV) infection are poorly characterized. In this study, we analyzed the host factors involved in CHIKV infection using genome-wide screening. Human haploid HAP1 cells, into which an exon-trapping vector was introduced, were challenged with a vesicular stomatitis virus pseudotype bearing the CHIKV E3 to E1 envelope proteins. Analysis of genes enriched in the cells resistant to the pseudotyped virus infection unveiled a critical role of N-sulfation of heparan sulfate (HS) for the infectivity of the clinically isolated CHIKV Thai#16856 strain to HAP1 cells. Knockout of NDST1 that catalyzes N-sulfation of HS greatly decreased the binding and infectivity of CHIKV Thai#16856 strain but not infectivity of Japanese encephalitis virus (JEV) and yellow fever virus (YFV). While glycosaminoglycans were commonly required for the efficient infectivity of CHIKV, JEV, and YFV, as shown by using B3GAT3 knockout cells, the tropism for N-sulfate was specific to CHIKV. Expression of chondroitin sulfate (CS) in NDST1-knockout HAP1 cells did not restore the binding of CHIKV Thai#16856 strain and the infectivity of its pseudotype but restored the infectivity of authentic CHIKV Thai#16856, suggesting that CS functions at later steps after CHIKV binding. Among the genes enriched in this screening, we found that TM9SF2 is critical for N-sulfation of HS and therefore for CHIKV infection because it is involved in the proper localization and stability of NDST1. Determination of the significance of and the relevant proteins to N-sulfation of HS may contribute to understanding mechanisms of CHIKV propagation, cell tropism, and pathogenesis.IMPORTANCE Recent outbreaks of chikungunya fever have increased its clinical importance. Chikungunya virus (CHIKV) utilizes host glycosaminoglycans to bind efficiently to its target cells. However, the substructure in glycosaminoglycans required for CHIKV infection have not been characterized. Here, we unveil that N-sulfate in heparan sulfate is essential for the efficient infection of a clinical CHIKV strain to HAP1 cells and that chondroitin sulfate does not help the CHIKV binding but does play roles at the later steps in HAP1 cells. We show, by comparing previous reports using Chinese hamster ovary cells, along with another observation that enhanced infectivity of CHIKV bearing Arg82 in envelope E2 does not depend on glycosaminoglycans in HAP1 cells, that the infection manner of CHIKV varies among host cells. We also show that TM9SF2 is required for CHIKV infection to HAP1 cells because it is involved in the N-sulfation of heparan sulfate through ensuring NDST1 activity.
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Heggelund JE, Mackenzie A, Martinsen T, Heim JB, Cheshev P, Bernardi A, Krengel U. Towards new cholera prophylactics and treatment: Crystal structures of bacterial enterotoxins in complex with GM1 mimics. Sci Rep 2017; 7:2326. [PMID: 28539625 PMCID: PMC5443773 DOI: 10.1038/s41598-017-02179-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 04/07/2017] [Indexed: 01/08/2023] Open
Abstract
Cholera is a life-threatening disease in many countries, and new drugs are clearly needed. C-glycosidic antagonists may serve such a purpose. Here we report atomic-resolution crystal structures of three such compounds in complexes with the cholera toxin. The structures give unprecedented atomic details of the molecular interactions and show how the inhibitors efficiently block the GM1 binding site. These molecules are well suited for development into low-cost prophylactic drugs, due to their relatively easy synthesis and their resistance to glycolytic enzymes. One of the compounds links two toxin B-pentamers in the crystal structure, which may yield improved inhibition through the formation of toxin aggregates. These structures can spark the improved design of GM1 mimics, either alone or as multivalent inhibitors connecting multiple GM1-binding sites. Future developments may further include compounds that link the primary and secondary binding sites. Serving as decoys, receptor mimics may lessen symptoms while avoiding the use of antibiotics.
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Affiliation(s)
- Julie Elisabeth Heggelund
- Department of Chemistry, University of Oslo, P.O. Box 1033, NO-0315, Blindern, Norway. .,School of Biomedical Sciences, University of Leeds, LS2 9JT Leeds, UK and School of Pharmacy, University of Oslo, P.O. Box 1068, NO-0316, Blindern, Norway.
| | - Alasdair Mackenzie
- Department of Chemistry, University of Oslo, P.O. Box 1033, NO-0315, Blindern, Norway.,Alere Technologies AS, Kjelsåsveien 161, NO-0884, Oslo, Norway
| | - Tobias Martinsen
- Department of Chemistry, University of Oslo, P.O. Box 1033, NO-0315, Blindern, Norway
| | - Joel Benjamin Heim
- Department of Chemistry, University of Oslo, P.O. Box 1033, NO-0315, Blindern, Norway
| | - Pavel Cheshev
- Universita' degli Studi di Milano, Dipartimento di Chimica, via Golgi 19, 20133, Milano, Italy.,Skolkovo innovation center, Office 229, OC Technopark bld. 2, Lugovaya str. 4, 143026, Moscow, Russia
| | - Anna Bernardi
- Universita' degli Studi di Milano, Dipartimento di Chimica, via Golgi 19, 20133, Milano, Italy
| | - Ute Krengel
- Department of Chemistry, University of Oslo, P.O. Box 1033, NO-0315, Blindern, Norway.
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25
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Hajishengallis G, Arce S, Gockel CM, Connell TD, Russell MW. Immunomodulation with Enterotoxins for the Generation of Secretory Immunity or Tolerance: Applications for Oral Infections. J Dent Res 2016; 84:1104-16. [PMID: 16304439 DOI: 10.1177/154405910508401205] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The heat-labile enterotoxins, such as cholera toxin (CT), and the labile toxins types I and II (LT-I and LT-II) of Escherichia coli have been extensively studied for their immunomodulatory properties, which result in the enhancement of immune responses. Despite superficial similarity in structure, in which a toxic A subunit is coupled to a pentameric binding B subunit, different toxins have different immunological properties. Administration of appropriate antigens admixed with or coupled to these toxins by oral, intranasal, or other routes in experimental animals induces mucosal IgA and circulating IgG antibodies that have protective potential against a variety of enteric, respiratory, or genital infections. These include the generation of salivary antibodies that may protect against colonization with mutans streptococci and the development of dental caries. However, exploitation of these adjuvants for human use requires an understanding of their mode of action and the separation of their desirable immunomodulatory properties from their toxicity. Recent findings have revealed that adjuvant action is not critically dependent upon the enzymic activity of the A subunits, and that the isolated B subunits may exert different effects on cells of the immune system than do the intact toxins. Interaction of the toxins with immunocompetent cells is not exclusively dependent upon their conventional ganglioside receptors. Immunomodulatory effects have been observed on dendritic cells, macrophages, CD4+ and CD8+ T-cells, and B-cells. Numerous factors—including the precise form of the toxin adjuvant, properties of the antigen, whether and how they are coupled, route of administration, and species of animal model—affect the outcome, whether this is enhanced humoral and cellular immunity, or specific induced tolerance toward the antigen.
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Affiliation(s)
- G Hajishengallis
- Department of Microbiology, Immunology, and Parasitology, and Center of Excellence in Oral and Craniofacial Biology, Louisiana State University Health Sciences Center, New Orleans, LA, USA
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Dogra N, Izadi H, Vanderlick TK. Micro-motors: A motile bacteria based system for liposome cargo transport. Sci Rep 2016; 6:29369. [PMID: 27377152 PMCID: PMC4932553 DOI: 10.1038/srep29369] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 06/15/2016] [Indexed: 11/18/2022] Open
Abstract
Biological micro-motors (microorganisms) have potential applications in energy utilization and nanotechnology. However, harnessing the power generated by such motors to execute desired work is extremely difficult. Here, we employ the power of motile bacteria to transport small, large, and giant unilamellar vesicles (SUVs, LUVs, and GUVs). Furthermore, we demonstrate bacteria–bilayer interactions by probing glycolipids inside the model membrane scaffold. Fluorescence Resonance Energy Transfer (FRET) spectroscopic and microscopic methods were utilized for understanding these interactions. We found that motile bacteria could successfully propel SUVs and LUVs with a velocity of 28 μm s−1 and 13 μm s−1, respectively. GUVs, however, displayed Brownian motion and could not be propelled by attached bacteria. Bacterial velocity decreased with the larger loaded cargo, which agrees with our calculations of loaded bacteria swimming at low Reynolds number.
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Affiliation(s)
- Navneet Dogra
- Department of Chemical &Environmental Engineering, Yale University, 10 Hillhouse Avenue, New Haven, CT, USA
| | - Hadi Izadi
- Department of Chemical &Environmental Engineering, Yale University, 10 Hillhouse Avenue, New Haven, CT, USA
| | - T Kyle Vanderlick
- Department of Chemical &Environmental Engineering, Yale University, 10 Hillhouse Avenue, New Haven, CT, USA
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27
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Wands AM, Fujita A, McCombs JE, Cervin J, Dedic B, Rodriguez AC, Nischan N, Bond MR, Mettlen M, Trudgian DC, Lemoff A, Quiding-Järbrink M, Gustavsson B, Steentoft C, Clausen H, Mirzaei H, Teneberg S, Yrlid U, Kohler JJ. Fucosylation and protein glycosylation create functional receptors for cholera toxin. eLife 2015; 4:e09545. [PMID: 26512888 PMCID: PMC4686427 DOI: 10.7554/elife.09545] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 10/26/2015] [Indexed: 12/14/2022] Open
Abstract
Cholera toxin (CT) enters and intoxicates host cells after binding cell surface receptors using its B subunit (CTB). The ganglioside (glycolipid) GM1 is thought to be the sole CT receptor; however, the mechanism by which CTB binding to GM1 mediates internalization of CT remains enigmatic. Here we report that CTB binds cell surface glycoproteins. Relative contributions of gangliosides and glycoproteins to CTB binding depend on cell type, and CTB binds primarily to glycoproteins in colonic epithelial cell lines. Using a metabolically incorporated photocrosslinking sugar, we identified one CTB-binding glycoprotein and demonstrated that the glycan portion of the molecule, not the protein, provides the CTB interaction motif. We further show that fucosylated structures promote CTB entry into a colonic epithelial cell line and subsequent host cell intoxication. CTB-binding fucosylated glycoproteins are present in normal human intestinal epithelia and could play a role in cholera. DOI:http://dx.doi.org/10.7554/eLife.09545.001 Cholera is a serious diarrheal disease that can be deadly if left untreated. It is caused by eating food, or drinking water, contaminated by the bacterium Vibrio cholerae. This bacterium can survive passage through the acidic conditions of the stomach. Inside the small intestine, V. cholerae attaches to the intestinal wall and starts producing cholera toxin. The toxin enters intestinal cells, causing them to release water and ions, including sodium and chloride ions. The salt-water environment created inside the intestine can, by osmosis, draw up to a further six liters of water into the intestine each day. This results in the copious production of watery diarrhea and severe dehydration. Cholera toxin is composed of six protein subunits, including five copies of cholera toxin subunit B (CTB). CTB subunits help the uptake of the toxin by intestinal cells, and it has long been reported that CTB subunits attach to intestinal cells by binding to a cell surface molecule called GM1. CTB subunits have a high affinity for GM1, yet recent work suggests CTB may not bind exclusively to GM1; one or more additional cell surface molecules may be directly involved in cholera toxin uptake. Wands et al. now reveal that numerous cell surface molecules are recognized by CTB, and that these molecules can assist cholera toxin uptake by host cells. Glycoproteins, proteins that are marked with sugar molecules, were shown to be the primary CTB binding sites on human colon cells, and it was the glycoprotein’s sugar component, not the protein itself, that interacted with CTB. Wands et al. discovered that in particular glycoproteins containing a sugar called fucose were largely responsible for CTB binding and toxin uptake. Together these findings reveal a previously unrecognized mechanism for cholera toxin entry into host cells, and suggest that fucose-containing or fucose-mimicking molecules could be developed as new treatments for cholera. DOI:http://dx.doi.org/10.7554/eLife.09545.002
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Affiliation(s)
- Amberlyn M Wands
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
| | - Akiko Fujita
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
| | - Janet E McCombs
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
| | - Jakob Cervin
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.,Mucosal Immunobiology and Vaccine Center, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Benjamin Dedic
- Department of Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Andrea C Rodriguez
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
| | - Nicole Nischan
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
| | - Michelle R Bond
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
| | - Marcel Mettlen
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - David C Trudgian
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
| | - Andrew Lemoff
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
| | - Marianne Quiding-Järbrink
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.,Mucosal Immunobiology and Vaccine Center, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Bengt Gustavsson
- Department of Surgery, University of Gothenburg, Gothenburg, Sweden
| | - Catharina Steentoft
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.,School of Dentistry, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Henrik Clausen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.,School of Dentistry, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hamid Mirzaei
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
| | - Susann Teneberg
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.,Department of Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Ulf Yrlid
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.,Mucosal Immunobiology and Vaccine Center, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Jennifer J Kohler
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
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28
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Swanson MD, Boudreaux DM, Salmon L, Chugh J, Winter HC, Meagher JL, André S, Murphy PV, Oscarson S, Roy R, King S, Kaplan MH, Goldstein IJ, Tarbet EB, Hurst BL, Smee DF, de la Fuente C, Hoffmann HH, Xue Y, Rice CM, Schols D, Garcia JV, Stuckey JA, Gabius HJ, Al-Hashimi HM, Markovitz DM. Engineering a therapeutic lectin by uncoupling mitogenicity from antiviral activity. Cell 2015; 163:746-58. [PMID: 26496612 DOI: 10.1016/j.cell.2015.09.056] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 06/05/2015] [Accepted: 09/29/2015] [Indexed: 10/22/2022]
Abstract
A key effector route of the Sugar Code involves lectins that exert crucial regulatory controls by targeting distinct cellular glycans. We demonstrate that a single amino-acid substitution in a banana lectin, replacing histidine 84 with a threonine, significantly reduces its mitogenicity, while preserving its broad-spectrum antiviral potency. X-ray crystallography, NMR spectroscopy, and glycocluster assays reveal that loss of mitogenicity is strongly correlated with loss of pi-pi stacking between aromatic amino acids H84 and Y83, which removes a wall separating two carbohydrate binding sites, thus diminishing multivalent interactions. On the other hand, monovalent interactions and antiviral activity are preserved by retaining other wild-type conformational features and possibly through unique contacts involving the T84 side chain. Through such fine-tuning, target selection and downstream effects of a lectin can be modulated so as to knock down one activity, while preserving another, thus providing tools for therapeutics and for understanding the Sugar Code.
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Affiliation(s)
- Michael D Swanson
- Division of Infectious Diseases, Department of Internal Medicine, Program in Immunology, University of Michigan, Ann Arbor, MI 48109, USA; Division of Infectious Diseases, Department of Medicine and UNC AIDS Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Daniel M Boudreaux
- Division of Infectious Diseases, Department of Internal Medicine, Program in Immunology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Biophysics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Loïc Salmon
- Department of Biophysics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jeetender Chugh
- Department of Biophysics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Harry C Winter
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jennifer L Meagher
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sabine André
- Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-Maximilians-University Munich, 80539 Munich, Germany
| | - Paul V Murphy
- School of Chemistry, National University of Ireland, Galway, Ireland
| | - Stefan Oscarson
- Centre for Synthesis and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland
| | - René Roy
- Department of Chemistry, Université du Québec à Montréal, Montréal, Québec H3C 3P8, Canada
| | - Steven King
- Division of Infectious Diseases, Department of Internal Medicine, Program in Immunology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Mark H Kaplan
- Division of Infectious Diseases, Department of Internal Medicine, Program in Immunology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Irwin J Goldstein
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - E Bart Tarbet
- Institute for Antiviral Research, Utah State University, Logan, UT 84322, USA
| | - Brett L Hurst
- Institute for Antiviral Research, Utah State University, Logan, UT 84322, USA
| | - Donald F Smee
- Institute for Antiviral Research, Utah State University, Logan, UT 84322, USA
| | | | | | - Yi Xue
- Department of Biochemistry, Duke University, Durham, NC 27710, USA
| | | | - Dominique Schols
- Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, University of Leuven, 3000 Leuven, Belgium
| | - J Victor Garcia
- Division of Infectious Diseases, Department of Medicine and UNC AIDS Center, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Jeanne A Stuckey
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Hans-Joachim Gabius
- Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-Maximilians-University Munich, 80539 Munich, Germany
| | - Hashim M Al-Hashimi
- Department of Biophysics, University of Michigan, Ann Arbor, MI 48109, USA; Department of Biochemistry, Duke University, Durham, NC 27710, USA.
| | - David M Markovitz
- Division of Infectious Diseases, Department of Internal Medicine, Program in Immunology, University of Michigan, Ann Arbor, MI 48109, USA.
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29
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Abstract
Heat-labile enterotoxins (LTs) of Escherichia coli are closely related to cholera toxin (CT), which was originally discovered in 1959 in culture filtrates of the gram-negative bacterium Vibrio cholerae. Several other gram-negative bacteria also produce enterotoxins related to CT and LTs, and together these toxins form the V. cholerae-E. coli family of LTs. Strains of E. coli causing a cholera-like disease were designated enterotoxigenic E. coli (ETEC) strains. The majority of LTI genes (elt) are located on large, self-transmissible or mobilizable plasmids, although there are instances of LTI genes being located on chromosomes or carried by a lysogenic phage. The stoichiometry of A and B subunits in holotoxin requires the production of five B monomers for every A subunit. One proposed mechanism is a more efficient ribosome binding site for the B gene than for the A gene, increasing the rate of initiation of translation of the B gene independently from A gene translation. The three-dimensional crystal structures of representative members of the LT family (CT, LTpI, and LTIIb) have all been determined by X-ray crystallography and found to be highly similar. Site-directed mutagenesis has identified many residues in the CT and LT A subunits, including His44, Val53, Ser63, Val97, Glu110, and Glu112, that are critical for the structures and enzymatic activities of these enterotoxins. For the enzymatically active A1 fragment to reach its substrate, receptor-bound holotoxin must gain access to the cytosol of target cells.
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30
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Balendra SI, Normando EM, Bloom PA, Cordeiro MF. Advances in retinal ganglion cell imaging. Eye (Lond) 2015; 29:1260-9. [PMID: 26293138 DOI: 10.1038/eye.2015.154] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 06/29/2015] [Indexed: 12/18/2022] Open
Abstract
Glaucoma is one of the leading causes of blindness worldwide and will affect 79.6 million people worldwide by 2020. It is caused by the progressive loss of retinal ganglion cells (RGCs), predominantly via apoptosis, within the retinal nerve fibre layer and the corresponding loss of axons of the optic nerve head. One of its most devastating features is its late diagnosis and the resulting irreversible visual loss that is often predictable. Current diagnostic tools require significant RGC or functional visual field loss before the threshold for detection of glaucoma may be reached. To propel the efficacy of therapeutics in glaucoma, an earlier diagnostic tool is required. Recent advances in retinal imaging, including optical coherence tomography, confocal scanning laser ophthalmoscopy, and adaptive optics, have propelled both glaucoma research and clinical diagnostics and therapeutics. However, an ideal imaging technique to diagnose and monitor glaucoma would image RGCs non-invasively with high specificity and sensitivity in vivo. It may confirm the presence of healthy RGCs, such as in transgenic models or retrograde labelling, or detect subtle changes in the number of unhealthy or apoptotic RGCs, such as detection of apoptosing retinal cells (DARC). Although many of these advances have not yet been introduced to the clinical arena, their successes in animal studies are enthralling. This review will illustrate the challenges of imaging RGCs, the main retinal imaging modalities, the in vivo techniques to augment these as specific RGC-imaging tools and their potential for translation to the glaucoma clinic.
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31
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Ji J, Griffiths KL, Milburn PJ, Hirst TR, O'Neill HC. The B subunit of Escherichia coli heat-labile toxin alters the development and antigen-presenting capacity of dendritic cells. J Cell Mol Med 2015; 19:2019-31. [PMID: 26130503 PMCID: PMC4549052 DOI: 10.1111/jcmm.12599] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Accepted: 03/25/2015] [Indexed: 02/05/2023] Open
Abstract
Escherichia coli's heat-labile enterotoxin (Etx) and its non-toxic B subunit (EtxB) have been characterized as adjuvants capable of enhancing T cell responses to co-administered antigen. Here, we investigate the direct effect of intravenously administered EtxB on the size of the dendritic and myeloid cell populations in spleen. EtxB treatment appears to enhance the development and turnover of dendritic and myeloid cells from precursors within the spleen. EtxB treatment also gives a dendritic cell (DC) population with higher viability and lower activation status based on the reduced expression of MHC-II, CD80 and CD86. In this respect, the in vivo effect of EtxB differs from that of the highly inflammatory mediator lipopolysaccharide. In in vitro bone marrow cultures, EtxB treatment was also found to enhance the development of DC from precursors dependent on Flt3L. In terms of the in vivo effect of EtxB on CD4 and CD8 T cell responses in mice, the interaction of EtxB directly with DC was demonstrated following conditional depletion of CD11c(+) DC. In summary, all results are consistent with EtxB displaying adjuvant ability by enhancing the turnover of DC in spleen, leading to newly mature myeloid and DC in spleen, thereby increasing DC capacity to perform as antigen-presenting cells on encounter with T cells.
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Affiliation(s)
- Jing Ji
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Kristin L Griffiths
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Peter J Milburn
- John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Timothy R Hirst
- John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Helen C O'Neill
- Faculty of Health Sciences and Medicine, Bond University, Gold Coast, QLD 4229, Australia
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32
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Ondondo B, Faulkner L, Williams NA, Morgan AJ, Morgan DJ. The B subunit of Escherichia coli enterotoxin helps control the in vivo growth of solid tumors expressing the Epstein-Barr virus latent membrane protein 2A. Cancer Med 2015; 4:457-71. [PMID: 25641882 PMCID: PMC4380971 DOI: 10.1002/cam4.380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 09/19/2014] [Accepted: 10/09/2014] [Indexed: 01/23/2023] Open
Abstract
Latent membrane protein 2A (LMP2A) is expressed on almost all Epstein–Barr virus (EBV)-associated tumors and is a potential target for immunotherapeutic intervention and vaccination. However, LMP2A is not efficiently processed and presented on major histocompatibility antigens class I molecules to generate potent cytotoxic T-lymphocytes (CTL) responses capable of killing these tumors. The B subunit of Escherichia coli enterotoxin (EtxB), causes rapid internalization and processing of membrane-bound LMP2A on EBV-infected B cells, and facilitates loading of processed-LMP2A peptides onto MHC class I. This re-directed trafficking/delivery of LMP2A to the MHC class I machinery enhances recognition and killing by LMP2A-specific CTL in vitro. To test the potential of EtxB to enhance immune targeting of LMP2A expressed in solid tumors, we generated a murine tumor model (Renca-LMP2A), in which LMP2A is expressed as a transgenic neoantigen on a renal carcinoma (Renca) cell line and forms solid tumors when injected subcutaneously into BALB/c mice. The data show that in BALB/c mice which have only low levels of peripheral Kd-LMP2A-specific CD8+ T cells, merely a transient inhibition of tumor growth is achieved compared with naïve mice; suggesting that there is suboptimal LMP2A-specifc CTL recognition and poorly targeted tumor killing. However, importantly, treatment of these mice with EtxB led to a significant delay in the onset of tumor growth and significantly lower tumor volumes compared with similar mice that did not receive EtxB. Moreover, this remarkable effect of EtxB was achieved despite progressive reduction in tumor expression of LMP2A and MHC class I molecules. These data clearly demonstrate the potential efficacy of EtxB as a novel therapeutic agent that could render EBV-associated tumors susceptible to immune control.
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Affiliation(s)
- Beatrice Ondondo
- The Jenner Institute, Old Road Campus Research Building, Roosevelt Drive, Oxford, Oxfordshire OX3 7DQ, United Kingdom
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33
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Bakhshi B, Boustanshenas M, Ghorbani M. A single point mutation within the coding sequence of cholera toxin B subunit will increase its expression yield. Iran Biomed J 2015; 18:130-5. [PMID: 24842138 PMCID: PMC4048476 DOI: 10.6091/ibj.1165.2014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Background: Cholera toxin B subunit (CTB) has been extensively considered as an immunogenic and adjuvant protein, but its yield of expression is not satisfactory in many studies. The aim of this study was to compare the expression of native and mutant recombinant CTB (rCTB) in pQE vector. Methods: ctxB fragment from Vibrio cholerae O1 ATCC14035 containing the substitution of mutant ctxB for amino acid S128T was amplified by PCR and cloned in pGETM-T easy vector. It was then transformed to E. coli Top 10F' and cultured on LB agar plate containing ampicillin. Sequence analysis confirmed the mature ctxB gene sequence and the mutant one in both constructs which were further subcloned to pQE-30 vector. Both constructs were subsequently transformed to E. coli M15 (pREP4) for expression of mature and mutant rCTB. Results: SDS-PAGE analysis showed the maximum expression of rCTB in both systems at 5 hours after induction and Western-blot analysis confirmed the presence of rCTB in blotting membranes. The expression of mutant rCTB was much higher than mature rCTB, which may be the result of serine-to-threonine substitution at position 128 of mature rCTB amino acid sequence created by PCR mutagenesis. The mutant rCTB retained pentameric stability and its ability to bind to anti- cholera toxin IgG antibodies. Conclusion: Point mutation in ctxB sequence resulted in over-expression of rCTB, probably due to the increase of solubility of produced rCTB. Consequently, this expression system can be used to produce rCTB in high yield.
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Affiliation(s)
- Bita Bakhshi
- Dept. of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mina Boustanshenas
- Dept. of Biology, Faculty of Basic Science, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Masoud Ghorbani
- Research and Production Complex, Pasteur Institute of Iran, Tehran, Iran
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Aigal S, Claudinon J, Römer W. Plasma membrane reorganization: A glycolipid gateway for microbes. Biochim Biophys Acta 2014; 1853:858-71. [PMID: 25450969 DOI: 10.1016/j.bbamcr.2014.11.014] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 09/27/2014] [Accepted: 11/11/2014] [Indexed: 02/08/2023]
Abstract
Ligand-receptor interactions, which represent the core for cell signaling and internalization processes are largely affected by the spatial configuration of host cell receptors. There is a growing piece of evidence that receptors are not homogeneously distributed within the plasma membrane, but are rather pre-clustered in nanodomains, or clusters are formed upon ligand binding. Pathogens have evolved many strategies to evade the host immune system and to ensure their survival by hijacking plasma membrane receptors that are most often associated with lipid rafts. In this review, we discuss the early stage molecular and physiological events that occur following ligand binding to host cell glycolipids. The ability of various biological ligands (e.g. toxins, lectins, viruses or bacteria) that bind to glycolipids to induce their own uptake into mammalian cells by creating negative membrane curvature and membrane invaginations is explored. We highlight recent trends in understanding nanoscale plasma membrane (re-)organization and present the benefits of using synthetic membrane systems. This article is part of a Special Issue entitled: Nanoscale membrane organisation and signalling.
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Affiliation(s)
- Sahaja Aigal
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestraße 1, 79104 Freiburg, Germany; BIOSS Centre for Biological Signaling Studies, Albert-Ludwigs-University Freiburg, Schänzlestraβe 18, 79104 Freiburg, Germany; International Max Planck Research School for Molecular and Cellular Biology (IMPRS-MCB), Max Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, 79108 Freiburg, Germany.
| | - Julie Claudinon
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestraße 1, 79104 Freiburg, Germany; BIOSS Centre for Biological Signaling Studies, Albert-Ludwigs-University Freiburg, Schänzlestraβe 18, 79104 Freiburg, Germany
| | - Winfried Römer
- Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestraße 1, 79104 Freiburg, Germany; BIOSS Centre for Biological Signaling Studies, Albert-Ludwigs-University Freiburg, Schänzlestraβe 18, 79104 Freiburg, Germany.
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Smith CA, Chauhan BC. Imaging retinal ganglion cells: enabling experimental technology for clinical application. Prog Retin Eye Res 2015; 44:1-14. [PMID: 25448921 DOI: 10.1016/j.preteyeres.2014.10.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 10/04/2014] [Accepted: 10/18/2014] [Indexed: 11/21/2022]
Abstract
Recent advances in clinical ophthalmic imaging have enhanced patient care. However, the ability to differentiate retinal neurons, such as retinal ganglion cells (RGCs), would advance many areas within ophthalmology, including the screening and monitoring of glaucoma and other optic neuropathies. Imaging at the single cell level would take diagnostics to the next level. Experimental methods have provided techniques and insight into imaging RGCs, however no method has yet to be translated to clinical application. This review provides an overview of the importance of non-invasive imaging of RGCs and the clinically relevant capabilities. In addition, we report on experimental data from wild-type mice that received an in vivo intravitreal injection of a neuronal tracer that labelled RGCs, which in turn were monitored for up to 100 days post-injection with confocal scanning laser ophthalmoscopy. We were able to demonstrate efficient and consistent RGC labelling with this delivery method and discuss the issue of cell specificity. This type of experimental work is important in progressing towards clinically applicable methods for monitoring loss of RGCs in glaucoma and other optic neuropathies. We discuss the challenges to translating these findings to clinical application and how this method of tracking RGCs in vivo could provide valuable structural and functional information to clinicians.
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Abstract
Immunoassays have been well established for many years as the cornerstone of detection technologies. These assays are sensitive, selective and, in general, highly resistant to interference from complex sample matrices when compared with nucleic acid-based tests. However, both antibody- and nucleic acid-based detection systems require a priori knowledge of the target and development of specific reagents; multiplexed assays can become increasingly problematic when attempting to detect a plethora of different targets, the identities of which are unknown. In an effort to circumvent many of the limitations inherent in these conventional assays, other recognition reagents are being explored as alternatives, or indeed as adjuncts, to antibodies for pathogen and toxin detection. This article will review a number of different recognition systems ranging in complexity from small molecules, such as nucleic-acid aptamers, carbohydrates and peptides, to systems as highly complicated as whole cells and organisms. All of these alternative systems have tremendous potential to achieve superior sensitivity, selectivity, and stability, but are also subject to their own limitations, which are also discussed. In short, while in its infancy, this field holds great promise for the development of rapid, fieldable assays that are highly complementary to existing antibody- and nucleic acid-based technologies.
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Affiliation(s)
- Miriam M Ngundi
- US Food and Drug Administration, N29 RM418 HFM-434 8800 Rockville Pike, Bethesda, MD 20892, USA.
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Wang H, Paton JC, Herdman BP, Rogers TJ, Beddoe T, Paton AW. The B subunit of an AB5 toxin produced by Salmonella enterica serovar Typhi up-regulates chemokines, cytokines, and adhesion molecules in human macrophage, colonic epithelial, and brain microvascular endothelial cell lines. Infect Immun 2013; 81:673-83. [PMID: 23250951 DOI: 10.1128/IAI.01043-12] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The principal function of bacterial AB5 toxin B subunits is to interact with glycan receptors on the surfaces of target cells and mediate the internalization of holotoxin. However, B subunit-receptor interactions also have the potential to impact cell signaling pathways and, in so doing, contribute to pathogenesis independently of the catalytic (toxic) A subunits. Various Salmonella enterica serovars, including Salmonella enterica serovar Typhi, encode an AB5 toxin (ArtAB), the A subunit of which is an ADP-ribosyltransferase related to the S1 subunit of pertussis toxin. However, although the A subunit is able to catalyze ADP-ribosylation of host G proteins, a cytotoxic phenotype has yet to be identified for the holotoxin. We therefore examined the capacity of the purified B subunit (ArtB) from S. Typhi to elicit cytokine, chemokine, and adhesion molecule responses in human macrophage (U937), colonic epithelial (HCT-8) cell, and brain microvascular endothelial cell (HBMEC) lines. Secretion of the chemokines monocyte chemotactic protein 1 (MCP-1) and interleukin 8 (IL-8) was increased in all three tested cell lines, with macrophage inflammatory protein 1α (MIP-1α), MIP-1β, and granulocyte colony-stimulating factor (G-CSF) also significantly increased in U937 cells. ArtB also upregulated the cytokines tumor necrosis factor alpha (TNF-α) and IL-6 in HBMECs and HCT-8 cells, but not in U937 cells, while intercellular adhesion molecule 1 (ICAM-1) was upregulated in HCT-8 and U937 cells and vascular cell adhesion molecule 1 (VCAM-1) was upregulated in HBMECs. Thus, ArtB may contribute to pathogenesis independently of the A subunit by promoting and maintaining a strong inflammatory response at the site of infection.
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Abstract
The heat-labile enterotoxins (HLTs) of Escherichia coli and Vibrio cholerae are classified into two major types on the basis of genetic, biochemical, and immunological properties. Type I and Type II HLT have been intensively studied for their exceptionally strong adjuvant activities. Despite general structural similarities, these molecules, in intact or derivative (non-toxic) forms, display notable differences in their mode of immunomodulatory action. The molecular basis of these differences has remained largely uncharacterized until recently. This review focuses on the Type II HLTs and their immunomodulatory properties which depend largely on interactions with unique gangliosides and Toll-like receptors that are not utilized by the Type I HLTs.
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Affiliation(s)
- George Hajishengallis
- University of Pennsylvania School of Dental Medicine, Department of Microbiology, Philadelphia, PA 19104, USA.
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Zhu H, Gomez CM. Further evidence for the role of IP 3R 1 in regulating subsynaptic gene expression and neuromuscular transmission. Channels (Austin) 2012; 6:65-8. [PMID: 22418950 DOI: 10.4161/chan.19175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The inositol 1,4,5-triphosphate IP 3R channel is highly expressed on specialized ER membrane, where it initiates a slow wave of Ca ( 2+) release from internal stores, allowing subcellular compartmentalization of Ca ( 2+) signals. In skeletal muscle, IP 3R 1 is also highly concentrated at some myonuclei, particularly near the NMJ. We have reported that in fully developed adult muscle, IP 3R 1 knockdown by siRNA increases synaptic strength at both pre- and post-synaptic sites of neuromuscular transmission, increasing both the amplitude and frequency of spontaneous quantal events and quantal content, as well as expression of AChR subunits and other NMJ-specific genes. Here, we demonstrate that reducing IP 3R 1 activity in mouse TA muscle by promoting hydrolysis locally of IP 3R 1 also amplifies expression of subsynaptic genes and transcription factors. Furthermore, using a retrograde tracer, cholera toxin B subunit, we find that siRNA-mediated silencing of IP 3R 1 in TA muscle increases vesicle trafficking. These studies suggest that postsynaptic IP 3R 1 activity regulates synaptic gene expression and neuromuscular transmission.
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Affiliation(s)
- Haipeng Zhu
- Department of Neurology, University of Chicago, Chicago, IL, USA
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Abstract
Vibrio cholerae is the causative agent of the diarrheal disease cholera. Although antibiotic therapy shortens the duration of diarrhea, excessive use has contributed to the emergence of antibiotic resistance in V. cholerae. Mobile genetic elements have been shown to be largely responsible for the shift of drug resistance genes in bacteria, including some V. cholerae strains. Quorum sensing communication systems are used for interaction among bacteria and for sensing environmental signals. Sequence analysis of the ctxB gene of toxigenic V. cholerae strains demonstrated its presence in multiple cholera toxin genotypes. Moreover, bacteriophage that lyse the bacterium have been reported to modulate epidemics by decreasing the required infectious dose of the bacterium. In this article, we will briefly discuss the disease, its clinical manifestation, antimicrobial resistance and the novel approaches to locate drug targets to treat cholera.
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Fazil MHUT, Kumar S, Farmer R, Pandey HP, Singh DV. Binding efficiencies of carbohydrate ligands with different genotypes of cholera toxin B: molecular modeling, dynamics and docking simulation studies. J Mol Model 2011; 18:1-10. [PMID: 21409571 DOI: 10.1007/s00894-010-0947-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 12/27/2010] [Indexed: 01/22/2023]
Abstract
Vibrio cholerae produces cholera toxin (CT) that consists of two subunits, A and B, and is encoded by a filamentous phage CTXΦ. The A subunit carries enzymatic activity that ribosylates ADP, whereas the B subunit binds to monosialoganglioside (GM1) receptor in epithelial cells. Molecular analysis of toxigenic V. cholerae strains indicated the presence of multiple ctxB genotypes. In this study, we employed a comparative modeling approach to define the structural features of all known variants of ctxB found in O139 serogroup V. cholerae. Modeling, molecular dynamics and docking simulations studies suggested subtle variations in the binding ability of ctxB variants to carbohydrate ligands of GM1 (galactose, sialic acid and N-acetyl galactosamine). These findings throw light on the molecular efficiencies of pathogenic isolates of V. cholerae harboring natural variants of ctxB in causing the disease, thus suggesting the need to consider ctxB variations when designing vaccines against cholera.
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Shamini G, Ravichandran M, Sinnott JT, Somboonwit C, Sidhu HS, Shapshak P, Kangueane P. Structural inferences for Cholera toxin mutations in Vibrio cholerae. Bioinformation 2011; 6:1-9. [PMID: 21464837 PMCID: PMC3064844 DOI: 10.6026/97320630006001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Accepted: 02/01/2011] [Indexed: 11/23/2022] Open
Abstract
Cholera is a global disease that has persisted for millennia. The cholera toxin (CT) from Vibrio cholerae is responsible for the clinical symptoms of cholera. This toxin is a hetero-hexamer (AB(5)) complex consisting of a subunit A (CTA) with a pentamer (B(5)) of subunit B (CTB). The importance of the AB(5) complex for pathogenesis is established for the wild type O1 serogroup using known structural and functional data. However, its role is not yet documented in other known serogroups harboring sequence level residue mutations. The sequences for the toxin from different serogroups are available in GenBank (release 177). Sequence analysis reveals mutations at several sequence positions in the toxin across serogroups. Therefore, it is of interest to locate the position of these mutations in the AB(5) structure to infer complex assembly for its functional role in different serogroups. We show that mutations in the CTA are at the solvent exposed regions of the AB(5) complex, whereas those in the CTB are at the CTB/CTB interface of the homo-pentamer complex. Thus, the role of mutations at the CTB/CTB interface for B(5) complex assembly is implied. It is observed that these mutations are often non-synonymous (e.g. polar to non-polar or vice versa). The formation of the AB(5) complex involves inter-subunit residue-residue interactions at the protein-protein interfaces. Hence, these mutations, at the structurally relevant positions, are of importance for the understanding of pathogenesis by several serogroups. This is also of significance in the improvement of recombinant CT protein complex analogs for vaccine design and their use against multiple serogroups.
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Affiliation(s)
- Gunasagaran Shamini
- Department of Biotechnology, AIMST University, Semeling 08100, Kedah, Malaysia
- Biomedical Informatics, Pondicherry, India 607402
| | | | - John T Sinnott
- Division of Infectious Disease, Department of Internal Medicine, Tampa General Hospital, University of South Florida, College of Medicine, Tampa, Florida 33606, USA
- Clinical Research Unit, Hillsborough Health Department,Tampa, Florida 33602, USA
| | - Charurut Somboonwit
- Division of Infectious Disease, Department of Internal Medicine, Tampa General Hospital, University of South Florida, College of Medicine, Tampa, Florida 33606, USA
- Clinical Research Unit, Hillsborough Health Department,Tampa, Florida 33602, USA
| | - Harcharan S Sidhu
- Department of Biotechnology, AIMST University, Semeling 08100, Kedah, Malaysia
| | - Paul Shapshak
- Division of Infectious Disease, Department of Internal Medicine, Tampa General Hospital, University of South Florida, College of Medicine, Tampa, Florida 33606, USA
- Department of Psychiatry and Behavioral Medicine, University of South Florida, College of Medicine, Tampa, Florida 33613, USA
| | - Pandjassarame Kangueane
- Department of Biotechnology, AIMST University, Semeling 08100, Kedah, Malaysia
- Biomedical Informatics, Pondicherry, India 607402
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Affiliation(s)
- Shuang Liang
- University of Louisville School of Dentistry, Oral Health and Systemic Disease, Louisville, KY, USA
| | - George Hajishengallis
- University of Louisville School of Dentistry, Oral Health and Systemic Disease, Louisville, KY, USA
- University of Louisville School of Medicine, Department of Microbiology and Immunology, Louisville, KY, USA
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Kato T, Kawaguchi A, Nagata K, Hatanaka K. Development of tetraphenylethylene-based fluorescent oligosaccharide probes for detection of influenza virus. Biochem Biophys Res Commun 2010; 394:200-4. [PMID: 20188703 PMCID: PMC7117542 DOI: 10.1016/j.bbrc.2010.02.155] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Accepted: 02/23/2010] [Indexed: 11/30/2022]
Abstract
Tetraphenylethylene (TPE) derivatives have strong fluorescence in aggregated state. We designed and synthesized a tetraphenylethylene derivative bearing alkyne groups which were used for combination by click chemistry. The new TPE compound bearing alkyne groups was used to synthesize fluorescence oligosaccharide probes which have lactosyl and 6′-sialyllactosyl moieties as ligands. We found that the TPE compounds bearing lactosyl and 6′-sialyllactosyl moieties were useful for detection of RCA120 and SSA lectins, respectively. Moreover, we have shown that TPE-based fluorescent oligosaccharide probe bearing 6′-sialyllactose moiety can be utilized as a “turn-on” fluorescent sensor for detection of influenza virus.
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Affiliation(s)
- Tomohisa Kato
- Japan Chemical Innovation Institute, 1-3-5 Jimbocho, Chiyoda-ku, Tokyo 101-0051, Japan.
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Stål P, Befrits R, Rönnblom A, Danielsson A, Suhr O, Ståhlberg D, Brinkberg Lapidus A, Löfberg R. Clinical trial: the safety and short-term efficacy of recombinant cholera toxin B subunit in the treatment of active Crohn's disease. Aliment Pharmacol Ther 2010; 31:387-95. [PMID: 19878149 DOI: 10.1111/j.1365-2036.2009.04185.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND The cholera toxin B subunit ameliorates experimentally induced colitis in mice. In humans, cholera toxin B subunit has never been tested in the treatment of Crohn's disease (CD). AIM To evaluate the safety and efficacy of treatment with recombinant cholera toxin B subunit of patients with CD. METHODS An open-label, multicentre, nonrandomized trial including 15 patients with mild/moderate CD. Patients received an oral solution of 5 mg recombinant cholera toxin B subunit three times weekly for 2 weeks. Reduction in CD Activity Index (CDAI) with >100 between baseline and days 15, 29, 42 and 70 defined clinical response. Patients with CDAI score < or = 150 were defined as being in remission. RESULTS A significant decrease in CDAI score was observed. Response rates were 40% in the full analysis set and 42% in the per protocol analysis. Two patients receiving adjuvant treatment after day 29 were excluded, after which 40% were in remission at 4 weeks and 30% at 8 weeks post-treatment. Mild side effects (arthralgia, headache and pruritus) were seen in 33% of patients. CONCLUSIONS Treatment with recombinant cholera toxin B subunit was safe. Approximately 40% of patients with active CD responded to treatment. Randomized studies are needed to establish the clinical efficacy of recombinant cholera toxin B subunit.
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Affiliation(s)
- P Stål
- Department of Gastroenterology and Hepatology Karolinska University Hospital, S-141 86 Stockholm, Sweden.
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Zhang C, Rausch D, Zhang W. Little heterogeneity among genes encoding heat-labile and heat-stable toxins of enterotoxigenic Escherichia coli strains isolated from diarrheal pigs. Appl Environ Microbiol 2009; 75:6402-5. [PMID: 19684170 DOI: 10.1128/AEM.00952-09] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
To examine whether the heat-labile enterotoxin gene in porcine enterotoxigenic Escherichia coli (ETEC) strains is as divergent as in human ETEC strains, we sequenced the heat-labile and heat-stable toxin genes from 52 and 33 porcine ETEC strains, respectively. We found that the STa gene is identical, that the LT gene has only two mutations in 4 (of 52) strains, and that both mutations cause a reduction in GM1 binding and toxicity.
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Abstract
Cholera toxin (Ctx) from Vibrio cholerae and its closely related homologue, heat-labile enterotoxin (Etx) from Escherichia coli have become superb tools for illuminating pathways of cellular trafficking and immune cell function. These bacterial protein toxins should be viewed as conglomerates of highly evolved, multi-functional elements equipped to engage the trafficking and signalling machineries of cells. Ctx and Etx are members of a larger family of A-B toxins of bacterial (and plant) origin that are comprised of structurally and functionally distinct enzymatically active A and receptor-binding B sub-units or domains. Intoxication of mammalian cells by Ctx and Etx involves B pentamer-mediated receptor binding and entry into a vesicular pathway, followed by translocation of the enzymatic A1 domain of the A sub-unit into the target cell cytosol, where covalent modification of intracellular targets leads to activation of adenylate cyclase and a sequence of events culminating in life-threatening diarrhoeal disease. Importantly, Ctx and Etx also have the capacity to induce a wide spectrum of remarkable immunological processes. With respect to the latter, it has been found that these toxins activate signalling pathways that modulate the immune system. This review explores the complexities of the cellular interactions that are engaged by these bacterial protein toxins, and highlights some of the new insights to have recently emerged.
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Affiliation(s)
- Lolke De Haan
- Department of Pathology and Microbiology, School of Medical Sciences, University of Bristol, United Kingdom
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Chen CG, Lu YT, Lin M, Savelyeva N, Stevenson FK, Zhu D. Amplification of immune responses against a DNA-delivered idiotypic lymphoma antigen by fusion to the B subunit of E. coli heat labile toxin. Vaccine 2009; 27:4289-96. [DOI: 10.1016/j.vaccine.2009.05.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2009] [Revised: 04/27/2009] [Accepted: 05/10/2009] [Indexed: 10/20/2022]
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Mikhalyov I, Gretskaya N, Johansson LBÅ. Fluorescent BODIPY-labelled GM1 gangliosides designed for exploring lipid membrane properties and specific membrane-target interactions. Chem Phys Lipids 2009; 159:38-44. [DOI: 10.1016/j.chemphyslip.2009.01.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Revised: 01/16/2009] [Accepted: 01/16/2009] [Indexed: 11/15/2022]
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Sachl R, Mikhalyov I, Hof M, Johansson LBA. A comparative study on ganglioside micelles using electronic energy transfer, fluorescence correlation spectroscopy and light scattering techniques. Phys Chem Chem Phys 2009; 11:4335-43. [PMID: 19458836 DOI: 10.1039/b821658d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ganglioside (G(M1)) micelles have been studied by means of three different techniques: fluorescence correlation spectroscopy (FCS), electronic energy transfer, as monitored by time-resolved fluorescence spectroscopy, as well as static and dynamic light scattering. The aggregation numbers obtained, 168 +/- 4, remain constant over a wide range of G(M1) concentrations (0.764-156 muM), are very consistent when using different donor-acceptor energy transfer pairs and have served as reference values in tests of the FCS method. It is recommended to calibrate the focal volume by using known dye concentrations. For this the rhodamine dye, 5-TAMRA, turns out to be most suitable. It is also shown that FCS provides correct values of the aggregation numbers, provided that the focal volume is calibrated by using updated values of the diffusion constant of Rhodamine 6G. These results also support recent methodological advances in FCS.
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Affiliation(s)
- Radek Sachl
- Department of Chemistry, Biophysical Chemistry, Umeå University, S-901 87, Umeå, Sweden
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